Range Object技术在图书馆自建数字文献资源中的应用实践

描述了Range Object的技术原理,并将其应用于图书馆自建数字文献资源的建设中。

CONTROL WORK IN CLOSE RANGE PHOTOGRAMMETRY

The purpose,classification,required accuracy and surveying methods of control work for close range photogrammetry have been briefly stated.The different methods for definition of space object coordinate system are also reviewed.It is suggested that the habitually-practised rotation angle system for aerophotogrammetry in China should be used for the future teaching and researching work in the close range photogrammetry,and that the rotation angle system for terrestrial deformation photogrammetry should be left out in order to avoid the confuse and reduce the amount of expanse for making softwares.It has been emphasized that there are three improtant aspects in the close range control work with high accuracy using the conventional method of engineering surveying:the use of standard scale for measurement of distance between two general stations,the accurate determination of start direction line between two general stations and the handling method of influence of 2 C change.A method for setting up industrial surveying control net with extra-high accuracy ±(0.05-0.20) mm is presented by the author.This kind of industrial control net is necessary for batch process of large industrial components with purposes of measurement,inspect and lofting.There are some special methods of control work in the close range photogrammetry,including two methods presented by the author.

Closed Range Composition Operators on a General Family of Function Spaces

In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F（p,q,s） and more generally on α-Besov type spaces F（p,αp-2,s） are given. We give a Carleson measure characterization on F （p, αp - 2, s） spaces, then we indicate how Carleson measures can be used to characterize boundedness and compactness of CФ on F（p,q,s） and F（p,αp- 2,s） spaces.

A Comparative Experimental Study on the Blast-Resistant Performances of Single and Multi-Layered Thin Plates Under Close-Range Airblast Loading

The performance of multilayered thin steel plates subjected to close-range air blasts has been experimentally studied and compared with that of monolithic plates made of the same material and having equal mass. In present experiments, multilayered plates are in-contact four-layered thin steel plates and two types of deformation/failure modes were observed for them. Comparisons concerning deformation/failure modes, strain distributions and energy absorptions between the multilayered plate and its monolithic counterpart were conducted. It is found that the multilayered plate is much superior to its monolithic counterpart in the ability to deform against blast loading. Furthermore, under intense airblast loading, the multilayered plate can not only absorb much more energy but also effectively reduce the secondary destruction ability of structural fragments in comparison with its monolithic counterpart.

THE SPECIFIC CHARACTER OF LIMIT ERRORS IN CLOSE RANGE PHOTOGRAMMETRY

Close_range photogrammetry is to determine the shape and size of the object,instead of it’s absolute position.Therefore,at first,any translation and rotation of the photogrammetric model of the object caused by whole geodesic,photographic and photogrammetric procedures in close_range photogrammetry could not be considered.However,it is necessary to analyze all the reasons which cause the deformations of the shape and size and to present their corresponding theories and equations.This situation,of course,is very different from the conventional topophotogrammetry.In this paper some specific characters of limit errors in close_range photogrammerty are presented in detail,including limit errors for calibration of interior elements for close_range cameras,the limit errors of relative and absolute orientations in close_range photogrammetric procedures,and the limit errors of control works in close_range photogrammetry.A theoretical equation of calibration accuracy for close_range camerais given.Relating to the three examples in this paper,their theoretical accuracy requirement of interior elements of camera change in the scope of ±(0.005～0.350) mm.This discussion permits us to reduce accuracy requirement in calibration for an object with small relief,but the camera platform is located in violent vibration environment.Another theoretical equation of relative RMS of base lines ( m S/S ) and the equation RMS of start direction are also presented.It is proved that the m S/S could be equal to the relative RMS of m Δ X / Δ X .It is also proved that the permitting RMS of start direction is much bigger than the traditionally used one.Some useful equations of limit errors in close_range photogrammetry are presented as well.Suggestions mentioned above are perhaps beneficial for increasing efficiency,for reducing production cost.

Direct Creation of Construction Drawings for Kwan-yin Statue by Close-Range Photogrammetry

In order to provide the model point accuracy of ±2 mm,an extra high accuracy industrial control net with four surveying piers with accuracy ±0.1 mm was set up around the model.Tens of orientation marks have been placed on the different parts and measured with accuracy ±0.2 mm from the above_mentioned piers.The main four stereopairs taken with the P31 camera around the model are simultaneously processed on the BC2 analytical plotter.The accuracy of absolute orientation is better than ±0.9 mm.Finally,about 300 sections construction drawings have been directly offered,and the close_range photogrammetric data has been used for the design and construction of the statue.

Digital close-range photogrammetric application to small-scale physical simulation experiment

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.131 mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

Multi-objective Collaborative Optimization for Scheduling Aircraft Landing on Closely Spaced Parallel Runways Based on Genetic Algorithms

A scheduling model of closely spaced parallel runways for arrival aircraft was proposed,with multi-objections of the minimum flight delay cost,the maximum airport capacity,the minimum workload of air traffic controller and the maximum fairness of airlines′scheduling.The time interval between two runways and changes of aircraft landing order were taken as the constraints.Genetic algorithm was used to solve the model,and the model constrained unit delay cost of the aircraft with multiple flight tasks to reduce its delay influence range.Each objective function value or the fitness of particle unsatisfied the constrain condition would be punished.Finally,one domestic airport hub was introduced to verify the algorithm and the model.The results showed that the genetic algorithm presented strong convergence and timeliness for solving constraint multi-objective aircraft landing problem on closely spaced parallel runways,and the optimization results were better than that of actual scheduling.

Short-ranged potential effects on the recurrence spectra of lithium M=1 atoms in parallel electric and magnetic fields

This paper presents recurrence spectra of highly excited lithium atoms with M = 1 state in parallel electric and magnetic fields at a fixed scaled energy ε = -0.03. Short-ranged potentials including ionic core potential and centrifugal barrier are taken into account. Their effects on the states and photo-absorption spectrum are analysed in detail. This demonstrates that the geometric features of classical orbits are of special importance for modulations of the spectral pattern. Thus the weak polarization as well as the reduction of correlation of electrons induced by short-ranged potentials give rise to the recurrence spectra of lithium M = 1 atoms more compact than that of the M = 0 one, which is in good agreement with the experimental prediction.

低碳视角下集成式纺织服装闭环供应链运作决策

纺织服装产业的蓬勃发展,不仅有效带动了社会经济的快速发展,同时也造成了废旧服装数量的日益剧增。为有效提高废旧服装回收效率及其利用率,兼顾供应链整体运营与生态环境的目标,文章设计分析了一个由供应商、制造商和零售商组成的三级纺织服装闭环供应链网络,其中零售商集成废旧服装的统一回收,制造商集成废旧服装的统一分类及再利用废旧服装的加工处理。鉴于服装回收处理过程中碳排放量高且分布不均这一现实问题,引入碳配额机制,以供应链整体收益和成本为目标,建立一个双目标决策优化模型,并对模型设计了约束求解方法。最后通过数值实验说明了本文所建模型的有效性和相应运营决策方案的合理最优性。相关研究结果表明:废旧纺织服装的回收处理尽管需要一定的运营成本,但从长期运营视角来看,其能够给供应链整体带来较大的潜在收益。零售商和制造商的集成化运营模式不仅可有效的降低供应链的整体运营成本,同时亦可有效提升供应链整体的协同运作效率。合理的碳配额机制可有效激励相关成员企业去绿色低碳运营,进而提升自身竞争力和可持续发展能力。相关研究成果不仅具有一定的理论价值,同时对政府和服装产业制定合理的碳配额机制,设计构建纺织服装闭环供应链网络具有一定的指导和借鉴意义。

基于功率转速双闭环的增程器发电功率动态控制策略

针对电动汽车内燃发电增程器发电功率动态控制存在的控制精度不高、响应滞后和反向超调等问题,提出并设计了一种结合功率/转速双闭环的增程器发电功率动态控制策略。该策略基于高效运行曲线进行发电功率的转矩/转速解耦,同时考虑了基于实际发电功率反馈的内燃机目标发电转矩修正、发电转矩转速动态协调修正。变工况发电试验结果表明,增程器发电过程中的发电功率最大正向超调为1.37 kW,最大反向超调为1.89 kW,稳态误差均小于0.01 kW,功率上升响应时间约为2.5 s,功率下降响应时间约为2.8 s,且工作点均在高效运行曲线附近。该增程器发电功率动态控制策略能够减少瞬态发电功率的响应滞后和反向超调的问题,在工程实践中具备可行性。

基于检测框下边沿的单目视觉车辆测距研究

对车辆测距是当今驾驶领域的热门研究方向。针对传统测距方法测距精度受到车型大小影响的问题以及前车存在的X轴偏移问题,提出了基于检测框下边沿中心点的车辆测距模型。该模型通过使用单目视觉摄像头及车辆检测算法获取前方车辆的位置信息,并通过车辆检测框得出的下边沿中心点坐标,以及相机安装的俯仰角信息综合建立了车辆测距模型,解决了车型大小带来的误差问题;通过构建三角函数模型,解决了前车相对于实验车辆存在的X轴分量问题,并优化改进了前车安全距离的判定方式;设定车尾矩形框中心点横坐标与车辆外接矩形框宽度的比值λ,根据λ取值分情况讨论,使该模型更符合场景应用需要。并提出了基于测距关键点的逆透视变换模型,减小了测距误差。实验表明,改进后测距模型的测距精度不受车型大小的影响且能考虑到前车位置的X轴分量问题,改进后的测距模型相对于传统测距模型,测距误差降低了约1.5%,且测距精度明显提高。

基于点云稀疏空间特征聚合激励的单阶段3D目标检测模型

针对目前基于点云的3D目标检测中单阶段体素法存在感受野固定、特征尺度单一,导致模型对点云特征学习不够充分、模型检测效果存在瓶颈等问题,提出了一种可端对端训练的基于体素的单阶段3D目标检测模型.首先,利用多尺度稀疏空间特征聚合模块,聚合点云在不同稀疏空间尺度上的特征,使特征充分保留点云的空间信息;然后,对特征进行分层激励,通过多尺度感受野对特征进行分层学习,强化特征的表达能力,降低噪声信息对检测结果的影响;最后,将特征输入检测头进行候选框的分类和回归.在公开的自动驾驶数据集KITTI上与主流单阶段3D目标检测模型进行了对比实验,包含对3类目标共9个的难度等级目标的检测.所提模型在其中5个等级中的平均准确率有明显提升,尤其对点云稀疏的目标,表现出较好的检测效果.实验结果表明,所提模型能够充分提取点云空间信息并有效地学习点云多尺度特征.

“视觉测量技术”课程建设的若干思考

视觉测量技术是一项新型测量技术,在国民经济和国防各领域有着广泛应用。但是在视觉测量技术快速发展和应用的同时,视觉测量技术的教学工作严重滞后,存在诸多问题。以培养学生创新性能力为指导思想、以规范视觉测量技术的概念和范畴为内涵、以从教学和工程应用的角度倡导视觉测量技术的开展为目标、以阐述视觉测量关键技术为内容,从“视觉测量技术”课程建设的意义、目的、指导思想、原则、内容规划等方面对“视觉测量技术”课程建设过程中涉及的问题进行了认真的思考和阐述。

基于改进北方苍鹰优化算法的封闭小区开放决策模型

为减少封闭小区开放过程中安全、环境与噪声等因素带来的影响,考虑小区开放的影响因素与费用值之间的关系,同时考虑小区出口和入口数量对内部交通疏散的影响,建立封闭小区是否开放的多目标优化模型。在北方苍鹰优化算法基础上,优化苍鹰的捕食行为,改进北方苍鹰优化算法对模型进行求解。通过虚拟路网验证模型和改进算法的有效性,计算结果表明,合理设置封闭小区的决策方式,可以减少车辆出行时间和出行总费用值,开放封闭小区能有效缓解交通压力。此外,将改进北方苍鹰优化算法(ENGO)与非支配排序遗传算法和社会工程优化器进行比较,研究结果能表明ENGO具有的优越性,相比其它两种算法,其反世代距离平均上升9.59%,超体积平均上升3.21%,运行时间平均下降5.88%。

近场爆炸荷载作用下装配式钢筋混凝土叠合梁动力响应数值分析

为研究装配式钢筋混凝土叠合梁的抗爆性能,采用显式动力有限元软件LS-DYNA建立了相应的数值模型,通过已有的钢筋混凝土现浇梁爆炸试验研究对数值模型进行了验证。采用验证了的数值模型对爆炸荷载作用下的叠合梁和现浇梁进行动力响应分析,考虑比例距离、炸药量、浇筑方式等参数变化对装配式钢筋混凝土叠合梁动力响应及抗爆性能的影响。结果表明:随比例距离减小或炸药量增大,梁破坏形态由弯曲破坏向弯剪破坏转变,梁位移响应加剧;叠合梁抗爆性能略低于现浇梁,但尚能满足规范要求。

近距离煤层垂向采空区高静储瞬态充水模式与解危技术

榆神府矿区侏罗纪煤田垂向层序上赋存多个煤层,当下层煤开采时,面临上部近距离采空区积水威胁,基于垂向采空区充水模式的综合解危技术是下层煤安全回采的关键。通过分析煤层顶板岩性组合、含隔水层以及导水裂缝带发育高度特征,形成了近距离煤层垂向采空区高静储瞬态充水模式,认为基岩风化带水、火烧区水、第四系萨拉乌苏组松散层潜水以及大气降水是浅层采空区的直接或间接补给水源,在上部煤层采空区中形成较高水位的静储量;近距离煤层下层煤开采时,导水裂缝带沟通上部采空区,高静储积水以瞬间溃入形式进入下层煤回采工作面。针对高静储采空区积水威胁,提出了“近距离煤层充水模型建立—采空区积水范围探测与积水量预计—垂向采空区积水解危—疏控效果评价”4阶段解危模式,形成了解危成功的判别标准,即当钻孔疏放量等于动态补给量时,可认定采空区静储量积水已基本疏放完毕,采空区积水威胁解除。该成果在神木惠宝煤矿成功应用,对类似条件下的矿井具有借鉴意义。

青年人近距离阅读纸质及电子文本对黄斑区微循环的短期影响

目的探讨持续近距离阅读相同内容的纸质文本和电子文本对健康青年人黄斑区微循环产生的短期影响。方法前瞻性使用光学相干断层扫描血管成像(OCTA)测量2021年5—10月就读于潍坊医学院的30名(60眼)健康在校大学生阅读纸质文本和电子文本1 h前后,黄斑区浅层视网膜血流密度(SVD)、深层视网膜血流密度(DVD)及脉络膜血流密度(CVD)和黄斑中心凹下脉络膜厚度(SFCT)的变化并进行对比。结果经过量化分析,阅读纸质文本1 h,SVD在中心凹的下降[(18.3±7.4)%,(17.4±7.2)%]和旁中心凹下方区域的下降[(50.2±4.2)%,(48.0±5.5)%],差异有统计学意义(Z=2.93,P=0.021;Z=3.25,P=0.007);在其他的采集区域中,干预前后SVD的改变差异无统计学意义(P>0.05)。阅读电子文本1 h后,CVD下降[(75.8±4.1)%,(74.7±4.9)%](t=2.36,P=0.022);SFCT下降(289.0±6.2,280.7±6.6)(t=2.35,P=0.022)。结论持续近距离阅读纸质文本1 h,会引起黄斑区浅层视网膜血流在短期内下降;持续近距离阅读电子文本1 h,会引起黄斑区脉络膜血流在短期内下降。这会增加一些眼底疾病的发病率。

基于自适应多曝光融合的高动态范围表面测量方法

为解决结构光测量高动态范围表面物体时出现局部过度曝光或曝光不足的问题,提出一种改进的多曝光融合方法,利用自适应曝光代替手动曝光,并对图像融合过程进行优化。首先,将初始曝光时间下拍摄的图像利用直方图进行分析,将被测物体表面反射率不同的区域分为若干组,分别计算出每个组别的最佳曝光时间;在此基础上,拍摄不同组别对应最佳曝光时间下投射白光和条纹的图像,并去除图像中超过设定阈值的高灰度值区域,再将投射白光处理后的图像制作成掩模图,与相同曝光时间下投射条纹处理后的图像相乘,进而对多组相乘后的图像进行亮度压缩与融合;最后,通过CLAHE算法提高融合后所生成条纹图的对比度与清晰度,并对条纹解相后进行点云重建和尺寸测量。实验结果表明:文中方法中自适应曝光相较于手动曝光具有高效性和准确性,U型卡、连接块、圆盘三个高动态范围表面物体的点云重建率分别高达99.98%、99.74%、99.76%,测量出的标准块阶梯高度差绝对误差为0.062 mm,相对误差仅为0.69%,该方法有效解决了高动态范围表面物体测量时点云缺失的问题,提高了三维轮廓的测量精度。